Which of the following is used to manufacture ethanol from starch?
- Saccharomyces
- Lactobacillus
- Azotobacter
- Penicillium
Answer
(1) Saccharomyces
Solution
As per NCERT, the yeast Saccharomyces cerevisiae (brewer's yeast) is used for fermenting malted cereals and fruit juices to produce ethanol.
⇒ Starch is first hydrolysed to sugars, which the yeast ferments to ethanol and CO2.
∴ Lactobacillus gives lactic acid, Azotobacter fixes nitrogen and Penicillium gives penicillin.
Answer: (1)